When the drug lord died in 1993, the elephants and giraffes found their way into several Colombian zoos. But more than two decades after Escobar was shot dead by Colombian National Police, the hippos still roam free. Only now, there are more than four.
Escobar's ranch, after years of neglect, was repurposed as a park, with local environmental authorities taking responsibility for the upkeep. The hippos have apparently thriven -- maybe a little too much. Officials estimate that there are some 50 or 60 hippos in the park.
But locals say they've expanded beyond the zoo walls.
"They found a creature in a river that they had never seen before, with small ears and a really big mouth," said Carlos Valderrama, a conservationist with the local group Webconserva. "The fishermen, they were all saying, 'How come there's a hippo here?'" he told the BBC. "We started asking around and of course they were all coming from Hacienda Napoles. Everything happened because of the whim of a villain."
Valderrama and others say the expanding hippo population -- as so many other invasive species do -- threatens the area's biodiversity.
As the hippos -- their lazy, pampered lives buoyed by the slow moving Magdalena River and an ideal climate devoid of drought -- continue to breed, the problem gets worse and worse. And authorities aren't sure what to do.
Some suggest rounding up all the loose hippos and building a park with suitable fences. That would cost some $500,000, a half-million that environmentalists say should be spent to protect native species. Others say the males should be euthanized.
The hippos aren't just a threat to biodiversity, but a threat to Colombian people. Hippos are dangerous animals, killing between 100 and 200 people every year. And while some zoos in the area have adopted the hippo pups, the adults remain free -- some of them lurking in public.
The conundrum at least has one person amused. For Mexican novelist Juan Pablo Villalobos, the hippos are a ripe metaphor.
"It's like a sign of what's happened in Colombia in the last 20 years," he told the BBC. "And this past is still present, and Colombians maybe don't know how to deal with this memory, with Pablo Escobar's heritage."
"All those contradictions are still alive there," Villalobos added, "and I think now in the most absurd way -- in hippos reproducing in a river."